Recently the fringes on the roof, window, door, fender, front grille, trunk and bonnet of an automobile and the side surfaces of a car body have been decorated with various moldings; among others, one with a hardened synthetic resin base or substrate, characterized by metallic luster, lightness and heat resistance, on the top side of which a stainless foil layer is integrated, is popular. Meanwhile, it is the conventional practice in auto manufacturing to apply a wax coating on the outside surface of a car body to protect it upon completion of its assembly and wipe off this coat just before delivery to the end user with a wax remover or a lamp oil. As a result, the solvent causes said synthetic resin molding base to crack ("solvent crack") and the stainless foil layer, i.e., the decorative surface of the molding is often crimped. Similar cracking is also caused by a surface active agent which has been applied for window glass cleaning.